Over the past nine years, the Yale Core Center for Musculoskeletal Disorders (YCCMD) has become a prominent feature of the scientific landscape at Yale. Collaborations with investigators at other institutions, our invited speakers program (YCCMD Seminar Series) and our website (http://info.med.yale.edu/intmed/yccmd), have given us a national presence. Our Center is dedicated to fostering research in disorders of skeletal tissue and muscle, with the ultimate goal of improving human health. The Center is particularly interested in supporting the development and comprehensive investigation of animal models of musculoskeletal disorders. To encourage and sustain these efforts, the Center has established core laboratories with expertise in whole-animal and skeletal-tissue analyses, molecular methods and bone-cell culture. These are the Molecular Core, the Physiology Core and the Cell Core. In its nine years of funding, Center membership has increased from 25 to 47 and the funding of our research base has increased from $7,267,249 annually to $34,795,969 annually in direct dollars. During the current funding cycle there have been over a hundred original research articles and numerous chapters and reviews published that have resulted from work carried out with direct Center support. The Center has awarded 29 pilot and feasibility projects over the past 9 years. Findings from these projects have resulted in 57 original articles and reviews and have been used to support successful applications for 22 new or competing continuations of externally funded awards. In the next five years we will follow the same successful blueprint that guided us through these past four years with carefully selected new initiatives planned in response to the changing needs of Centers members. Among the planned new initiatives are to offer BAG recombineering in the Molecular Core and to offer stem cell isolation and culture in the Cell Core. The Physiology Core plans to offer microCT analysis, specialized tissue stains for bone and an extended panel of bone turnover markers. The YCCMD has been and remains committed to a vibrant interdisciplinary and challenging community of biomedical scientists at Yale.